1. Field of the Invention
The present invention relates to: a portable communications terminal, exemplified by a portable telephone; an information display device for use with a portable communications terminal, a personal computer, or the like; and an input device and the like using the same.
2. Related Art of the Invention
In recent years, advances have been made for portable telephones incorporating information communications capabilities, as exemplified by the widespread use of terminals equipped with Internet connection service capabilities enabling the use of electronic mail and other services such as i-MODE and eZ-Web, a kind of web site or content which is suitable to a small screen having a small amount of pixels which is capable to be quipped on a portable telephone.
FIG. 14(a) shows the construction of a portable telephone equipped with information communications capabilities according to the prior art. As shown, the portable telephone 1400 comprises an input part 1401 having a numeric keypad, etc. for entering a telephone number, characters, and other information, a display part 1402 for displaying a telephone number, received information, etc., a speaker 1403 for hearing voice from the remote party, and a microphone 1404 for inputting voice.
In this type of portable telephone 1400, the display part 1402, usually constructed from a small transmissive liquid crystal display, is provided between the speaker 1403 and the microphone 1404, and electronic mail messages, i-MODE web pages, etc. are displayed on this display part 1402.
However, when using this type of portable telephone 1400 as an information communications terminal, the limited screen size of the display part 1402 can become a problem; that is, content specifically created for portable terminals designed for i-MODE or like service can be displayed for viewing without any problem, but when it comes to displaying other content such as web sites that are suitable to a large screen generally used for desktop PC or the like on a network, the resolution of the screen is not sufficient and the content is difficult to view on the display.
To address this problem, there has been proposed in recent years a portable telephone that uses a projection type, high resolution micro-display instead of the conventional liquid crystal display; as shown in FIG. 14(b), the micro-display 1411 is mounted near the microphone 1404 of the portable telephone 1410 and used to display information, or the projection micro-display is attached externally to the main unit of the portable telephone via a cable, and the portable telephone is used as an information terminal by operating it using the numeric keypad, etc. The projection micro-display is constructed using a small display in combination with an optical system, and produces a virtual image for viewing in a space distanced from the display, thereby achieving a large screen, high resolution virtual image display. With this technology, the display as small as about 1 cm square in size can present, when mounted in position as stated above, a high resolution image equivalent, for example, to SVGA (800×600 pixels) for viewing near the viewer's eye.
On the other hand, for an input device designed for use with such a near-to-eye display device, there has previously been proposed a construction in which an operator's motion is detected by a camera or by an electromuscular signal detector worn on the operator's body, and the thus detected motion is converted into a command to control an information processing device.
However, in the case of the prior art portable telephone shown in FIG. 14(b), since the micro-display is integrally mounted in the portable telephone main unit, it has not been possible to adjust the distance between the eye and the display screen; furthermore, since numeric keys or other input buttons are used to operate the portable telephone, the operator has had to stop looking into the projection micro-display 1411 and view the input part 1401 to operate the keys or buttons, and it has therefore been difficult to operate the portable telephone while viewing the screen, unlike the case of a personal computer.
On the other hand, when the micro-display is connected externally to the portable telephone, since the portable telephone is operated with one hand and the micro-display with the other hand, both hands have had to be used for operation, presenting a problem in operability.
As for the input device, since the detector for detecting the operator's motion and the information processing device controlled by a command associated with the detected motion are separate units, the prior art has had the problems that the entire system comprising the detector and the information processing device occupies a relatively large space, that the convenience of portability has to be compromised, and that when the detector and the information processing device are disposed at some distance away from each other because of the available space, it is difficult to verify whether the information processing device is being controlled properly by the commands associated with the operator's motions.